replace travis-ci

[mpranj]

We need to replace travis-ci since it is shut down completely and this was the only CI environment for go-elektra.

[markus2330]

go-elektra (and elektrad) does not have high priority, we might even remove it for 1.0.

@raphi011 or do you have some time to make everything work again?

[mpranj]

go-elektra works afaik, I tested it locally. We just need to fix the CI.

I don't know about the elektrad state right now.

[markus2330]

Or we finally integrate go-elektra into the main repo. Which will be also very useful for the many API changes we plan to do...